Head mounting and positioning apparatus for random access disc memory systems

Claim 1

IN COMBINATION WITH A PAIR OF SPACED PARALLEL RECORDING DISCS JOURNALLED ON A SUPPORT FOR ROTATION ABOUT A COMMON CENTRAL AXIS, AN ARM EXTENDING RADIALLY BETWEEN SAID DISCS ALONG A SECOND AXIS PARALLEL TO THE DISCS, MEANS SLIDABLY MOUNTING SAID ARM ON SAID SUPPORT FOR RADIAL MOVEMENT BETWEEN SAID DISCS, SAID SUPPORT FOR SPRING MEANS FOR RESILIENTLY MOUNTING SAID HEADS ON OPPOSITE SIDES OF SAID ARM IN POSITIONS ADJACENT CONFRONTING RECORDING SURFACES OF SAID DISCS, SAID SPRING MEANS COMPRISING DEPENDING PORTIONS EXTENDING NORMAL TO THE SECOND AXIS, A PAIR OF RETRACTION BARS LOCATED ON OPPOSITE SIDES OF THE DEPENDING PORTIONS, PIVOTED FOR ROTATION ABOUT AXES PARALLEL TO SAID SECOND AXIS, AND ROTATABLE BETWEEN A FIRST POSITION ENGAGING SAID DEPENDING PORTIONS TO FORCE SAID HEADS AWAY FROM THE SURFACES OF THE DISCS AND A SECOND POSITION DISENGAGED FROM THE DEPENDING PORTIONS, AND LINKAGE MEANS INTERCONNECTING SAID RETRACTION BARS FOR SELECTIVELY AND SIMULTANEOUSLY ROTATING THEM BETWEEN THEIR FIRST AND SECOND PORTIONS.